When the performance lineup includes such names as Emmylou Harris, Vince Gill, Rodney Crowell, Guy Clark and Nanci Griffith, it's worth taking a trip to Music City for an evening at the famous Ryman Auditorium. The "Old Friends: The Concert" is slated for May 15th. Though all these artists have managed to work together in some form or fashion, they've never shared the stage together at the same time.